Instead of filling our lives with things that might make us happy in the moment like video games, movies, tasty foods, fancy clothes, vacations, or a nice car, he recommends that we live life by using The Meter. The idea is simple yet powerful:

Selling drugs to kids would register a -10.

Playing a video game would register a 0.

Working to cure a disease would register a +10.

Marty thinks we should live our lives by always asking ourselves how our next activity would register on the meter.

I think that just about everyone will be unable to register a +10 or even a positive number on the meter with every block of time they have, no matter how hardworking or well-meaning they are. However, I do see the value of repeatedly considering whether our next actions will add to, take away, or do nothing for society. I also can see how productivity directed at making the world a better place might lead to genuine personal happiness and fulfillment.